He arches into the thrust, head thrown back and a tense whine escaping him, teeth closed on his bottom lip. It doesn't hurt, not really, not after the stretching Neil's given him, but it's sudden and it's intense, and for a moment he feels faintly dizzy.

He lets out a shuddering breath, trying once again to relax into it, and Neil's hand on his throat--where something like that would normally be cause for annoyance or alarm--is weirdly comforting, rising and falling with the rise and fall of his breathing.